Calculators Math ap Calculator

OK, In high school, I'll be taking math up till AP Calculus BC, and in University, I'll be going in sciences, and will need a lot of math.
I'm planning to buy a TI-89 Titanium. I want one, widely used, and will easily fulfill all my needs. Is this a good choice?

Yea, its a good choice. You can check your answers in calculus, algebra, etc. It has tons mathematical functions becuase of its built in CAS (computer algebra system). In fact, I recommended this particular TI calculator to many of my friends.

I haven't used the TI-89, so cannot offer a first hand opinion.. Here's an electrical engineer's opinion/review of this calculator. He finds it cumbersome, lacking in documentation, and sites several problem areas.

In my high-school (calc BC) and undergraduate calculus courses, use of the TI-89 was often not allowed because of its more advanced functions (eg. symbolic integration/differentiation). For personal use it would probably be great, but I've gotten along well so far with just a TI-84 Plus.

I would choose TI-84 Plus. These are expensive calculators and if you will only use this calculator on one exam, it's no use. TI-89 is also very complicated. Why wouldn't the TI-89 Titanium be allowed in college?